2.1 Earth's Crust in Motion


Vocabulary


stress: a type of force that acts on rocks to change the shape or volume.
earthquake: shaking from the seismic waves from the movement of rock under Earth's surface.
shearing: stress that forces a mass of rock in two different(opposite) directions.
tension:stress force that pulls on rocks, making it so its thinner in the middle.
compression: force that squeezes rocks until they break.
deformation: any kind of change in volume or shape of rocks in earth's crust.
fault: a break in earth's crust where slabs of crust slip past each other
strike-slip fault: rocks on either side of a fault slip in an opposite sideways motion.
normal fault: the fault is at an angle so one block of rock lies above the fault while the other block lies below fault.
hanging wall: the piece of rock that hangs at the upper part.
footwall: the piece of rock that lies below.
fault-block mountain: when normal faults uplift a block of rock
reverse fault: has the same parts of a normal fault, but the blocks move along a reverse fault.
folds: bends in rock that form when compression shortens and thickens part of Earth's crust.
anticline: a fold in rock that bends upwards like a bridge.
syncline: a fold in rock that bends down into a dip.

plateau: a big piece of flat land higher than sea level.

Outline


Types of Stress

  • Shearing
    • causes masses of rock to slip
  • Tension
    • stretches the rock, making it thinner
  • Compression
    • pushes rock make middle bend upwards

Kinds of Faults

  • Strike slip fault
    • two rocks slip past each other in a sideways, up, or down motion.
  • Normal fault
    • the fault is at an angle
      • one block of rock lies above the fault
      • other is below the fault
  • Reverse fault
    • same structure as a normal fault
    • reverse position
    • blocks in opposite direction

Friction along faults

  • anticlines and syncline

KHKZsyn-anti.jpgDiagram


KHKZsyn-anti.jpg
KHKZsyn-anti.jpg
Anticlines and syliclines

KHKZsyn-anti.jpg